This invention relates to an alkylation method for the preparation of diarylalkanes using a synthetic porous crystalline catalyst composition.
Diarylalkanes, such as diphenylmethane, benzyltoluene, and the like, are normally made by the alkylation of aromatic hydrocarbons (e.g., benzene, naphthalene, biphenyls) with aryl halides and alcohols. Diarylalkanes are useful as dielectric impregnants for capacitors, as intermediates in the manufacture of electric insulating, traction and rubber processing oils, as intermediates in the production of pesticides, plasticizers, pharmaceuticals, dyes, and lubricants.
Alkylation reactions are usually carried out at atmospheric pressure with the reactants in the liquid phase, utilizing acid catalysts (e.g. H.sub.2 SO.sub.4, BF.sub.3, ALCl.sub.3), metal oxides, or strongly acidic exchange resins. Select aluminosilicates have also been used in the preparation of diarylalkanes.
U.S. Pat. No. 2,402,092 discloses the alkylation of aromatic hydrocarbons with aralkyl halides over silica.
U.S. Pat. No. 3,941,706 describes the preparation of dicyclopentylalkylbenzene functional fluids by treating a lower alkyl substituted benzene such as toluene or ethylbenzene with cyclopentene employing a Friedel-Crafts type catalyst such as aluminum chloride.
U.S. Pat. No. 4,251,675 relates to the preparation of diphenylmethane by reacting benzene and benzyl chloride in the presence of a Friedel-Crafts type catalyst such as ferric chloride.
U.S Pat. No. 4,339,621 discloses the preparation of unsubstituted and alkyl substituted diphenylmethanes by reacting benzene with an alpha-chloromethyl benzene in the presence of sulfuric acid and a cationic surfactant.
U.S. Pat. No. 4,689,436 describes the preparation of alkenyl-aromatic hydrocarbon derivatives by reacting an aromatic hydrocarbon (e.g., benzene, toluene, xylene, tetralin, etc.) with an alkenyl substituted aromatic hydrocarbon (e.g., styrene) in the presence of a heteropolyacid (e.g., phosphotungstic acid, silicomolybodic acid, etc.) and/or a salt thereof.
European Patent Application serial No. 202,752 discloses the preparation of alkylated multi-ring aromatic compounds by reacting the corresponding multi-ring aromatic compound with an alkylating agent, preferably a xylene, in the presence of a zeolite such as ZSM-5, ZSM-11, mordenite, zeolite L and ZSM-4 (zeolite omega).